3D Printing can be a household thing in near future. No doubt, you might have heard about 3D Printing more often nowadays. The technology is deemed to be a catalyst for another industrial revolution. The days when 3D printing will be used for mass productions in manufacturing sector may not be far. 3D Printing, which has been in the industry since the late 1980s, earlier more popular by the term Additive Printing, is bound to leap beyond modelling and prototyping application.
There is not one way, 3D printing can be carried out. Currently there are seven standard manufacturing processes recognized by the American Society for Testing and Materials (ASTM). All of these processes are additive in nature and differ only in the way layers are laid out. Efforts are on to innovate new processes other than the additive types but currently only additive manufacturing processes are applicable to 3D printing. Let’s see how Material Extrusion process implements 3D printing.Being an extrusion process, FDM involves a hot end and a cold end. The hot end is an extrusion head to which the fabrication material is supplied by unwinding plastic filament or metal wire off a coil.
Vat Photo polymerisation is another popular 3D printing process. The process is based on hardening of photopolymers on exposure to the ultraviolet radiation. The photopolymer is in the form of a liquid resin filled inside a Vat, that is why, it got the name Vat Photo polymerisation.Stereolithography was invented in 1986 by Charles Hull at the time when he founded his company 3D Systems. For Stereolithography a Vat is filled with the liquid photopolymer resin. The 3D model is built on a platform which dips into the resin to a depth of a single layer. The height of a single layer is usually 0.05 mm to 0.15 mm. An ultraviolet light source which direct the radiation onto resin by reflection from motor controlled mirrors is mounted at the top of the apparatus.
Binder jetting is one of the seven recognized standard 3D Printing processes. The technique is copyrighted by the name 3DP technology. It was developed at Massachusetts Institute of Technology (MIT) in 1993. Later on, the license of the technology was obtained by Z Corporation in 1995.This is a powder based 3D printing technique and uses a powder like building material to be joined by liquid binder for 3D printing. In a typical apparatus for binder jetting, there are two chambers where one chamber is filled with powdered building material to feed into the other chamber and the second chamber is used for realizing the 3D model. The 3D model is built by gluing together the powdered building material using the liquid binder.
The Powder Bed Fusion is another powder based 3D printing technique. Unlike the binder jet 3D printing that uses a binder liquid to glue together building material’s particles, in powder bed fusion techniques, the particles of building material for 3D part are fused together by the application of heat or electron beam.All the PBF techniques are similar in operation except that the method of fusing the powder material differs in them. In Selective Laser Sintering, a laser head is used to project high power laser beam on the powder material to melt the particles and fuse them together.
Directed Energy Deposition (DED) is a 3D printing technology specifically used to create 3D models from metals and alloys. The technique can be applied for making 3D parts or objects from polymers, glass or ceramics but is not popular for that. This technique is quite commonly used for repair of existing 3D models built using metal or alloy.Many times the technique is used for adding extensions to existing metallic models. The typical apparatus for Directed Energy Deposition 3D Printing consist of a head for material wire supply which can move along multiple axis and an electron beam projector or high power laser beam projector which melts the fed wire through directing the high power radiation.
Sheet lamination is one of the seven recognized 3D Printing methods. The process uses sheets of building material which are cut through laser or knife and the sheets are joined one after the other either by using an adhesive or by wielding the laser cut sheets together to form the 3D object. The process is also called ultrasonic additive manufacturing (UAM) in case the building material used is metal sheets.The apparatus for UAM variation of the sheet lamination process has a cylindrical sonotrode to which the material sheet is coiled. The sonotrode is rotated to feed the material sheet onto a building platform.
Material Jetting is one of the standard 3D printing technology that has scope and design pattern suitable for the desktop version of 3D printers as industrial 3D printers. The technology fabricates a 3D part just like an inkjet printer prints a two-dimensional image. The 3D model is built on a target surface to which droplets or continuous fluids of the building material are dropped layer by layer and each layer is then cured with ultraviolet radiation to get it solidified. The term “Drop on Demand” is used for referring the drop by drop wise fabrication of 3D model in the technology’s context. A typical apparatus for material jetting 3D printing has printer head consisting of two nozzles and an UV source.